High-speed high-resolution signal processing for multicell silicon drift detectors

A data acquisition system is presented for X-ray spectroscopic and imaging applications. It has the capability to process the signals of up to 120 silicon drift detector channels in parallel. The signal processing comprises a 12-bit digitization at 1 MSps per detector channel, an optical readout at 2.488 Gbit/s, and an online histogramming with a counting depth of 32 bits per energy class and channel. The user gains full system control and VMEbus-based data access by an additional bidirectional optical link and a commercial VME controller, respectively. The system´s performance tests show that the integral nonlinearity and the rms noise do not exceed ±0.4 LSB and 0.58 LSB, respectively. The mean rms noise over all channels amounts to 0.55 LSB. The modular system´s setup assures an upgradability to 1860 detector channels in steps of 120